README.md: Align rogueutil information
Import err 1.0.1
Remove extraneous level of bulleting
Reference the correct project mailing lists
Use single angle brackets for links

I had two present so that angle brackets would appear in the web view of
this file. I wanted this because I like to view links with angle
brackets around them in the terminal, and I thought it would be good to
see them in the web view of README.md as well. I now realize this to be
a wrong thing to do, because of the difference in the way links are
presented on the web compared to a file viewed in a temrinal. It is fine
with me that links appear simply as links in the web view of the file.
Remove MAX() and MIN() macros

The MAX() macro was never used and the MIN() macro was only used once.
The place it was used already has an explanatory comment, which helps to
offset the ugliness of the ternary operator.
Use parentheses around usages of comma operator

Without the parentheses, at a glance these statements may look like they
just say `return ewarn(...)`, and the actual value being returned isn't
noticed. The presence of parentheses brings attention to the end of the
Reformat error function documentation strings
Remove excess lines from err.c
Keep the comment lines in the $NAVIPAGE_SH example under 72 chars
Use a real TLD in the $NAVIPAGE_SH example
Split up $server into $user and $server in the $NAVIPAGE_SH example
Include stdarg.h in err.h

This prevents a compiler warning that it doesn't know what va_list is.
Use rsync in $NAVIPAGE_SH example
Improve comment spacing in $NAVIPAGE_SH example
Add cls() calls

These calls are needed, else files with less lines than the amount of
rows in the terminal will display with the lines that were previously on
the terminal (whether previous commands executed, or the contents of a
previous buffer being displayed) still present.
Change 'track' to 'follow' in README.md
Add ewarn() and warn() calls to error_buffer() calls
Make use of new err.c error functions

Work still to do: get rid of error_buffer().